One Phoenix police officer was shot and killed and another one was in critical condition following a gun battle with a fugitive near a busy Valley intersection Monday afternoon.

The veteran officer, who was not identified, died at St. Joseph's Hospital a few hours after the shootout, said Phoenix police Chief Daniel Garcia. Choking with emotion, Garcia said the officer had been with the department for 21 years.

Garcia said the other officer, who has been on the force for nine years, was "fighting for his life." By early Monday evening, that officer was out of surgery and recovering in the intensive care unit. Police said they are "hopeful he will make a full recovery."

The chief called it "a tragic and violent day for the city of Phoenix and the Phoenix Police Department."

"I ask the citizens of Phoenix to keep both families and officers in their prayers," Garcia told reporters.

Officers and friends gathered at the hospital through the evening to pay their respects.

The suspect, who was identified Monday night as William Thornton, 28, was shot and killed. Thornton served time at the Arizona Department of Corrections Lewis prison for dangerous drug violation and resisting arrest convictions.

Phoenix police Sgt. Steve Martos said the two officers on fugitive apprehension detail were pursuing a suspect wanted on a felony warrant at about 3:20 p.m.

Thornton, realizing he was being followed, collided with several other vehicles at 43rd Avenue and Bethany Home Road, Martos said. Two people were injured in the crash - a 50-year-old man and an 83-year-old woman.

"After the collision, the suspect fled on foot around a building," Martos said.

The officers got out of their car and chased Thornton into the parking lot near the TitleMax. The suspect started shooting at the two officers, Martos said.

A third undercover officer with the fugitive apprehension squad appeared on the scene and heard gunshots.

The officer saw the suspect shooting at the two other officers, Martos said. The third officer shot and killed Thornton, according to Martos.

"These particular detectives are some of the best detectives that we have," Martos said. "Their job is to look for and arrest felony individuals, people who are wanted for violent offenses. They have a lot of tactical knowledge. It is an inherently dangerous job for officers."

CBS 5 News spoke with a woman who was nearby.

"We were just right by the door and all of a sudden it was just like, 'Boom, boom, boom, boom, boom,'" said neighbor Samantha Wheeler.

Wayne Monton owns a shoe store across the street from where this happened.

"People were kind of in shock, stunned, looking in disbelief," he said. "No one could believe this was happening. I couldn't believe it was happening."

Officers swarmed the scene, which is roped off with crime tape during an investigation that could last through the night.

The intersection will remain closed for hours, police said. Officers urged motorists to avoid the area.

Phoenix Mayor Greg Stanton, who was in Mexico, rushed back to Phoenix Monday night. Right after the shooting, he tweeted, "Nicole and I and the entire City of Phoenix family are praying hard for our two police officers and their families."

A short time later, he issued the following statement:

"Today's event is a tragic reminder of the incredible dangers our police officers face each and every day. Phoenix has lost a 21-year veteran of our Police Department who willingly put his life in harm's way to keep us safe, and was actively working to take the worst kind of violent criminal off our streets. Another officer, a nine-year veteran of the force, continues to fight for his life.

"This is the most difficult kind of day for our City. I ask that all of Phoenix join Nicole and me and pray for these officers, their families and loved ones, as well as every one of our brave men and women in uniform."

Arizona Gov. Jan Brewer sent two tweets.

"I was heartbroken to hear of the senseless tragedy today that took the life of a @phoenixpolice officer and left another officer wounded."

Her other tweet said:

"I send my deepest prayers and condolences to them and their families and I ask our state to do the same this evening. #PHXPD"

People wishing to donate money for the fallen officer's family can click here to reach the 100 Club of Arizona's website.

It was the second officer-involved shooting of the day.

At about 4 a.m. Monday, police responded to an alarm at Legendary Guns of the West Inc., near 19th Avenue just north of Camelback Road.

One suspect fired a handgun as he ran away after being confronted by police and an officer fired at him when he pointed a gun at the officer, investigators said.

Two people were taken into custody and officers searched several neighborhoods for a third suspect.

Stay with cbs5az.com and CBS 5 News for updates on this developing story.

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